Typically, gas turbine engines include a compressor for compressing air, a combustor for mixing the compressed air with fuel and igniting the mixture, and a turbine blade assembly for producing power. Combustors often operate at high temperatures that may exceed 2,500 degrees Fahrenheit. Typical turbine combustor configurations expose turbine vane and blade assemblies to high temperatures. As a result, turbine vanes and blades must be made of materials capable of withstanding such high temperatures, or must include cooling features to enable the component to survive in an environment which exceeds the capability of the material. Turbine engines typically include a plurality of rows of stationary turbine vanes extending radially inward from a shell and include a plurality of rows of rotatable turbine blades attached to a rotor assembly for turning the rotor.
Typically, the turbine airfoils are exposed to high temperature combustor gases that heat the airfoils. The airfoils include internal cooling systems for reducing the temperature of the airfoils. Many conventional cooling systems include linear exit slots at the trailing edge, as shown in FIG. 10. The exit slots are linear with uniform cross-sections in the chordwise direction. These blades typically experience high temperatures in the trailing edge region. The linear exit slots foster minimal contact with the cooling fluid flowing therethrough, thereby resulting in limited effectiveness. Thus, a need exists for improved cooling efficiency at the airfoil trailing edge.